It's always the way. You look forward to a series of Doctor Who and then as soon as it arrives, it's almost over. This week, the traditional two-part season finale begins with 'The Pandorica Opens'.

From across space and time, the Doctor's friends send him a warning; the Pandorica - "a box, a cage, a prison" of fairytale - is opening. It contains "a warrior, soaked in the blood of a billion galaxies. The most feared being in all the cosmos". As fleets of his foes mass in the sky above Stonehenge, has the Doctor finally met his match?